Abscission regulation by NoCut requires the Srs2/PARI helicases. DNA missegregation events that persist beyond cytokinesis engage the NoCut pathway to protect the genome. Dam et al. show that the Sr2s helicase participates in the sensing of missegregated DNA in yeast, and a similar role is proposed for PARI, the human homolog of Srs2. Sensing of the missegregated DNA by these helicases is proposed to initiate a signalling cascade through Aurora B, thereby inhibiting mediators of abscission such as the ESCRT machinery. Parallel induction of actin patches contributes to stabilize the DNA bridges, thus avoiding catastrophic DNA damage.